Nontrivial spin textures induced remarkable topological Hall effect and extraordinary magnetoresistance in kagome magnet TmMn₆Sn₆

Kagome magnets RMn6Sn6 (R = lanthanides) manifest novel topological phases and field-induced transitions, owing to the interplay between strong correlations and geometrical frustration among the corner-sharing-triangle intralayers. Here we report the magnetometry and magnetoelectric transport properties of TmMn6Sn6 single crystal, which coexists with Tm and Mn magnetic sublattices. We reveal that this compound displays multiple magnetic structures with the increase of in-plane magnetic field. The combination of non-collinear magnetic structure and real-space Berry curvature leads to a remarkable topological Hall effect over an extensive temperature range. The in-plane magnetic transition is accompanied by a large magnetoresistance effect of -32 similar to -17% from 10 K to 300 K at 7 T, and the magnetoresistance manifests two peaks with increasing the inplane field. These observations suggest a robust Mn - Tm magnetic coupling, which provides a nontrivial ferrimagnetic network for the further investigation of new emergent topological magnetic structures.